The present invention relates to an ink jet recording apparatus for discharging ink from a nozzle and adhering the ink to a recording medium.
An ink jet recording apparatus achieves high speed printing of high picture quality at low cost, and is employed as an information recording apparatus for office automation use or personal use. The ink jet recording apparatus is widely used in a copying machine, a facsimile, a printer, or a word processor.
Various technologies have been proposed regarding such an ink jet recording apparatus, and technologies adequate to high-speed recording, high resolution, and full color are now studied earnestly.
The ink jet recording method comprises steps of discharging color material and adhering and fixing the material to a recording medium such as paper. For discharging the color material, a following energy generating means is used; a means using an exothermic resistor such as an electrothermal energy conversion element, a means using a piezoelectric element such as electromechanical energy conversion element, or an electrostatic type means using electric energy.
FIG. 6 is a schematic perspective view of an essential part of one example of typical ink jet recording apparatuses. FIG. 7 is a side sectional view of a recording head and a carriage in the ink jet recording apparatus of FIG. 6.
In FIG. 6 and FIG. 7, carriage 102 loaded with recording head 101 is slidably supported by carriage shaft 103 and guide rail 104, and fixed to belt 108 suspended via belt holder 109 between drive pulley 106 and idler pulley 107 that are mounted to drive motor 105. In this structure, a rotation of drive motor 105 is converted to a reciprocating motion of belt 108, and carriage 102 is slid in the X direction (main scan direction). During the sliding of carriage 102, color material discharged from recording head 101 adheres to recording medium 111 based on a signal sent from electric wire 110.
Conveying roller 112, a plurality of pinch rollers 113, delivering roller 114, and a polarity of spurs 115 move recording medium 111 in the Y direction (sub scan direction) for serial scan, and the ink jet recording is performed.
When the recording head mounted to the carriage becomes clogged to require a replacement of a component in the ink jet recording apparatus discussed above, the disassembling of the apparatus into a plurality of components, the replacement of the component, and subsequent accurate reassembling are required. Thus, much time and much work are disadvantageously required for the replacement.
This problem is solved if the entire ink jet recording apparatus is replaced, but this method is not economical and requires management such as holding or disposing of the removed apparatus.
The present invention addresses the problem discussed above and aims to provide an ink jet recording apparatus allowing easy replacement of its recording head.
The ink jet recording apparatus of the present invention comprises the following components:
(a) a recording head for discharging ink in different colors from a plurality of nozzles;
(b) an ink tank for supplying the ink to the recording head;
(c) a carriage loaded with the recording head;
(d) a carriage-driving device for driving the carriage;
(e) a bendable electric wire that is bent from an apparatus body and mounted to the recording head, and passes a printing signal to the recording head while changing the bent position in response to the movement of the carriage; and
(f) a carriage frame for arranging the carriage, the carriage-driving device, the recording head, and the electric wire at predetermined positions to form a unit. The carriage can reciprocate in parallel with the main scan direction along the longitudinal direction of the carriage frame. The carriage-driving device comprises a drive pulley, an idler pulley, a drive motor, and a belt. The carriage is fixed to the belt, and the belt is suspended between the drive pulley and the idler pulley and is reciprocated by the drive motor for driving the drive pulley.
Thanks to this structure, the entire carriage frame can be replaced without removing respective components, thereby facilitating the replacement of the recording head.
In the ink jet recording apparatus of the present invention, also, a projection that projects in the forming direction of a nozzle surface for discharging ink of the recording head is formed on the carriage frame. This structure prevents the nozzle surface of a recording head built in newly in the replacing work from contacting with a mounting surface and damaging.
In the ink jet recording apparatus, also, the drive motor and the carriage are disposed on opposite sides of the carriage frame, and a total weight on the carriage side is less than the weight on the drive motor side. In this structure, the carriage frame tilts with the drive motor lying on the lower side, so that the recording head does not contact with the mounting surface. The nozzle surface of the newly built-in recording head in the replacing work can therefore be protected.
A seated height of the carriage is less than the height of the carriage frame in the ink jet recording apparatus, so that the recording head does not contact with the mounting surface and the nozzle surface of the newly built-in recording head in the replacing work can therefore be protected.
A seated height of the electric wire is less than the height of the carriage frame in the ink jet recording apparatus, so that the carriage frame protects the electric wire from an impact to stabilize the electric connection.
A seated height of a feed tube for supplying ink to the ink tank is less than the height of the carriage frame in the ink jet recording apparatus, so that the load on a joint between the feed tube and the ink tank is reduced and the ink supplying can be stabilized.
The electric wire is coupled to the feed tube for supplying ink in the apparatus, so that a head substrate coupling part of the electric wire and an ink tank coupling part of the feed tube do not contact with the mounting surface and therefore the maintenance is facilitated.
A mechanism for applying a tension to the belt is mounted to the carriage frame in the apparatus, so that the replacing work is allowed without removing components.
A position detecting board for detecting positional information of the carriage and a detecting sensor for detecting a position of the carriage are mounted to the carriage frame in the apparatus, so that the replacing work is allowed without removing the position detecting board and the detecting sensor.
An adjusting lever for adjusting a clearance between the recording head and the recording medium is mounted to the carriage frame in the apparatus, so that the replacing work is allowed without removing the adjusting lever.